Radio-frequency (RF) electromagnetic radiation has been used for diagnosis and imaging of body tissues, examples of which may be found in PCT Patent Publication No. WO2011/067623, now expired, US Patent Publication Nos. 2009/0299175, now U.S. Patent No. 8,352,015, and 2009/0240133 (abandoned), and U.S. Pat. No. 4,926,868 (expired), U.S. Pat. No. 5,766,208 (expired) and U.S. Pat. No. 6,061,589 (expired). Each of those disclosures is herein incorporated by reference in its entirety.